/* app.css - Steganography Page Styles */

:root {
    --bg-color: #111115;
    --text-primary: #f5f5f7;
    --text-secondary: #a1a1aa;
    --accent-color: #6366f1;
    --accent-hover: #4f46e5;
    --card-bg: rgba(255, 255, 255, 0.05);
    --card-border: rgba(255, 255, 255, 0.1);
    --input-bg: rgba(0, 0, 0, 0.3);
    --input-border: rgba(255, 255, 255, 0.15);
    --error-color: #ef4444;
    --success-color: #10b981;
}

body {
    margin: 0;
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-primary);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

.container {
    width: 100%;
    max-width: 600px;
    margin: 40px auto;
    padding: 0 20px;
    box-sizing: border-box;
}

/* Header */
.app-header {
    text-align: center;
    margin-bottom: 2rem;
}

.app-header h1 {
    font-size: 2.5rem;
    font-weight: 600;
    margin: 0 0 0.5rem 0;
    background: linear-gradient(135deg, #a5b4fc, #6366f1);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.app-header p {
    color: var(--text-secondary);
    font-size: 0.95rem;
    line-height: 1.5;
    margin: 0;
}

/* Mode Selector */
.mode-selector {
    display: flex;
    gap: 10px;
    margin-bottom: 1.5rem;
    background: rgba(0, 0, 0, 0.2);
    padding: 6px;
    border-radius: 999px;
    border: 1px solid var(--card-border);
    justify-content: center;
}

.mode-btn {
    padding: 10px 24px;
    background: transparent;
    border: none;
    color: var(--text-secondary);
    font-family: inherit;
    font-size: 0.9rem;
    font-weight: 500;
    cursor: pointer;
    border-radius: 999px;
    transition: all 0.3s ease;
}

.mode-btn:hover {
    color: var(--text-primary);
}

.mode-btn.active {
    background: rgba(255, 255, 255, 0.1);
    color: white;
    box-shadow: 0 2px 8px rgba(0,0,0,0.2);
}

/* Tabs */
.tabs {
    display: flex;
    gap: 10px;
    margin-bottom: 1rem;
    background: var(--card-bg);
    padding: 6px;
    border-radius: 12px;
    border: 1px solid var(--card-border);
}

.tab-btn {
    flex: 1;
    padding: 12px 16px;
    background: transparent;
    border: none;
    color: var(--text-secondary);
    font-family: inherit;
    font-size: 0.95rem;
    font-weight: 500;
    cursor: pointer;
    border-radius: 8px;
    transition: all 0.3s ease;
}

.tab-btn:hover {
    color: var(--text-primary);
    background: rgba(255, 255, 255, 0.05);
}

.tab-btn.active {
    background: var(--accent-color);
    color: white;
    box-shadow: 0 4px 12px rgba(99, 102, 241, 0.3);
}

/* Cards */
.glass-card {
    background: var(--card-bg);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border: 1px solid var(--card-border);
    border-radius: 16px;
    padding: 24px;
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.3);
    transition: opacity 0.3s ease, transform 0.3s ease;
}

.tab-content {
    display: none;
    opacity: 0;
    transform: translateY(10px);
}

.tab-content.active {
    display: block;
    opacity: 1;
    transform: translateY(0);
}

/* Animations for mode switching */
.mode-section {
    animation: fadeIn 0.3s ease forwards;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(-5px); }
    to { opacity: 1; transform: translateY(0); }
}

/* Inputs & Forms */
.input-group {
    margin-bottom: 1.25rem;
}

.input-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-size: 0.9rem;
    font-weight: 500;
    color: var(--text-secondary);
}

/* Custom File Upload */
.file-upload {
    position: relative;
    display: inline-block;
    width: 100%;
    cursor: pointer;
}

.file-upload input[type="file"] {
    position: absolute;
    left: 0;
    top: 0;
    right: 0;
    bottom: 0;
    width: 100%;
    height: 100%;
    opacity: 0;
    cursor: pointer;
    z-index: 2;
}

.file-custom {
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 14px 16px;
    background-color: var(--input-bg);
    border: 1px dashed var(--input-border);
    border-radius: 10px;
    color: var(--text-secondary);
    font-size: 0.95rem;
    transition: all 0.2s ease;
    text-align: center;
}

.file-upload:hover .file-custom {
    border-color: var(--accent-color);
    color: var(--text-primary);
    background-color: rgba(99, 102, 241, 0.1);
}

textarea {
    width: 100%;
    padding: 14px;
    background-color: var(--input-bg);
    border: 1px solid var(--input-border);
    border-radius: 10px;
    color: var(--text-primary);
    font-family: inherit;
    font-size: 0.95rem;
    resize: vertical;
    box-sizing: border-box;
    transition: border-color 0.2s ease;
}

textarea:focus {
    outline: none;
    border-color: var(--accent-color);
}

textarea[readonly] {
    background-color: rgba(0, 0, 0, 0.5);
    cursor: default;
}

textarea::placeholder {
    color: #52525b;
}

/* Image Preview */
.image-preview {
    width: 100%;
    max-height: 250px;
    object-fit: contain;
    margin-top: 1rem;
    border-radius: 8px;
    border: 1px solid var(--card-border);
    background: rgba(0, 0, 0, 0.2);
}

/* Buttons */
.primary-btn {
    width: 100%;
    padding: 14px 20px;
    background: var(--accent-color);
    color: white;
    border: none;
    border-radius: 10px;
    font-size: 1rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s ease;
    margin-top: 0.5rem;
}

.primary-btn:hover {
    background: var(--accent-hover);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(99, 102, 241, 0.4);
}

.primary-btn:active {
    transform: translateY(0);
}

/* Messages */
.error-msg, .success-msg {
    margin-top: 1rem;
    font-size: 0.9rem;
    text-align: center;
    border-radius: 8px;
    padding: 10px;
    display: none;
}

.error-msg {
    background: rgba(239, 68, 68, 0.1);
    color: var(--error-color);
    border: 1px solid rgba(239, 68, 68, 0.2);
}

.success-msg {
    background: rgba(16, 185, 129, 0.1);
    color: var(--success-color);
    border: 1px solid rgba(16, 185, 129, 0.2);
}

/* Responsive constraints */
@media (max-width: 480px) {
    .container {
        margin: 20px auto;
    }
    
    .app-header h1 {
        font-size: 2rem;
    }
    
    .glass-card {
        padding: 20px 16px;
    }
}